UPDATE

config/__init__.py

@@ -1,3 +1,15 @@
+try:
+    import pymysql
+except ImportError:  # pragma: no cover - optional fallback when mysqlclient is unavailable
+    pymysql = None
+else:  # pragma: no cover - import side effect
+    # Django 5's MySQL backend checks the mysqlclient version string during import.
+    # PyMySQL exposes a legacy compatibility version, so override it before installing
+    # the MySQLdb shim.
+    pymysql.version_info = (2, 2, 1, "final", 0)
+    pymysql.__version__ = "2.2.1"
+    pymysql.install_as_MySQLdb()
+
 try:
     from .celery import app as celery_app
 except ImportError:  # pragma: no cover - fallback for test environments

config/settings.py

@@ -12,7 +12,21 @@ load_dotenv()
 
 BASE_DIR = Path(__file__).resolve().parent.parent
 LOG_DIR = Path(os.environ.get("LOG_DIR", BASE_DIR / "logs"))
-LOG_DIR.mkdir(parents=True, exist_ok=True)
+
+
+def _can_use_file_logging(log_dir: Path) -> bool:
+    try:
+        log_dir.mkdir(parents=True, exist_ok=True)
+        probe_file = log_dir / ".write_test"
+        with probe_file.open("a", encoding="utf-8"):
+            pass
+        probe_file.unlink(missing_ok=True)
+        return True
+    except OSError:
+        return False
+
+
+FILE_LOGGING_ENABLED = _can_use_file_logging(LOG_DIR)
 
 SECRET_KEY = os.environ.get("SECRET_KEY", "django-insecure-dev-only")
 DEBUG = os.environ.get("DEBUG", "0") == "1"
@@ -192,29 +206,34 @@ LOGGING = {
             "class": "logging.StreamHandler",
             "formatter": "standard",
         },
-        "file": {
-            "class": "logging.handlers.TimedRotatingFileHandler",
-            "filename": str(LOG_DIR / "app.log"),
-            "when": "midnight",
-            "backupCount": 14,
-            "encoding": "utf-8",
-            "formatter": "standard",
-        },
     },
     "loggers": {
         "django": {
-            "handlers": ["console", "file"],
+            "handlers": ["console"],
             "level": os.environ.get("DJANGO_LOG_LEVEL", "INFO"),
             "propagate": False,
         },
         "rag": {
-            "handlers": ["console", "file"],
+            "handlers": ["console"],
             "level": os.environ.get("RAG_LOG_LEVEL", "INFO"),
             "propagate": False,
         },
     },
     "root": {
-        "handlers": ["console", "file"],
+        "handlers": ["console"],
         "level": os.environ.get("ROOT_LOG_LEVEL", "INFO"),
     },
 }
+
+if FILE_LOGGING_ENABLED:
+    LOGGING["handlers"]["file"] = {
+        "class": "logging.handlers.TimedRotatingFileHandler",
+        "filename": str(LOG_DIR / "app.log"),
+        "when": "midnight",
+        "backupCount": 14,
+        "encoding": "utf-8",
+        "formatter": "standard",
+    }
+    LOGGING["loggers"]["django"]["handlers"].append("file")
+    LOGGING["loggers"]["rag"]["handlers"].append("file")
+    LOGGING["root"]["handlers"].append("file")